Tomographic determination of cerebral blood flow during attacks of cluster headache.

A rapidly rotating single-photon emission tomograph was used to study regional cerebral blood flow (rCBF) by 133-Xenon inhalation in 18 patients with cluster headache. Measurements were performed in all patients in the resting state. The patients were given alcohol and/or nitroglycerin to provoke an attack of cluster headache. In eight patients it was possible to obtain satisfactory measurements during their cluster headache attack. All patients had a normal resting CBF with a normal age regression. During the headache phase, no significant changes of mean CBF from baseline occurred. There were no focal changes in the individual patient, but the mean rCBF in all eight patients showed significantly increased rCBF in the central, basal region and a small part of the right parietotemporal region. These changes we interpret as pain activation. It may be concluded that changes in rCBF are not likely to play a pathophysiological role in the development of cluster headache attacks.